JOLY AND MUSSEY, ON HETEROGENESIS. 49 



the decoction, which otherwise contained very little ; 3, that 

 the air was not renewed. 



The criterion apparatus presented the same animalcules, 

 but they were far more numerous and more lively, which is to 

 be attributed, without doubt, to the more abundant supply 

 and easy renewal of the air in contact with the decoction. 



In support of these results might be cited those which were 

 obtained on the authors repeating, with the utmost care and 

 with some modifications of their own, the experiments of 

 Schultze, of Schwann, and of Mantegazza. 



In the experiment performed according to the methods of 

 Schultze and of Schwann, they obtained both Microphytes 

 and Microzoa in the one case, and Microzoa only in the 

 other, although the air employed had been purified by 

 sulphuric acid, potass, or heat, and sometimes by two of these 

 agents. With respect to Mantegazza's experiment,* which the 

 authors think has been too little regarded in France, it has 

 afforded in their hands results very nearly identical with those 

 stated by that physiologist ; that is to say, abundance of 

 Bacterium termo and Bacterium catenula. 



* Fide 'Giornale del 11. Istituio Lombardo,' torn, iii, p. 467, " Richerche 

 suUa Generazioue degli Infusoria di P. Mantegazza," Milano, 1851. 



